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|airport : zzz.airport
|agl single value : 0
|common carrier : air carrier
|Make Model Name
|Operating Under FAR Part
|company : air carrier
|maintenance : lead technician
|technician : airframe
technician : powerplant
|company : air carrier
|oversight : supervisor
|aircraft equipment problem : critical
maintenance problem : improper maintenance
maintenance problem : improper documentation
non adherence : published procedure
non adherence : far
|other other : 1
|none taken : detected after the fact
|contributing factor : manuals
performance deficiency : non compliance with legal requirements
performance deficiency : scheduled maintenance
performance deficiency : testing
|Maintenance Human Performance
Chart Or Publication
When I reported in for work on feb/xa/08; I was informed that mr X (supervisor) had signed off a vacuum leak check job planning card xyz for the left engine fuel feed system. This item was signed off under amm reference. The amm states: task 3) task: engine fuel feed lines/coupling vacuum test. A) general: 1) the engine fuel-feed pressure test can be used as an alternative to this task. But; as far as the next shift work crew knows; the job card did not get accomplished. And we have been instructed that the air carrier X job card always takes priority over the amm. The maintenance personnel all know that the vacuum check is incorporated for a good reason. The design of this system must meet certain criteria in order to ensure proper fuel feed to the engines in case of electrical failure. Evidently the time involved in ensuring this does not always fit into the time the aircraft is down for maintenance. The fuel tanks have been closed. No further action taken. This aircraft is presently in heavy maintenance. The crew had worked on this system for several days and hydraulic system cannot be activated until the fuel system is closed for hydraulic cooling. Ensure it is not the job of a supervisor to sign off 'gray area' or 'good enough' functional; leak; or any check; especially when there is a job card with step-by-step instructions for aircraft maintenance work acceptance. Also; include inspection on such checks; who have been removed from most.
Original NASA ASRS Text
Title: A B737-400 LEAD TECH REPORTS ABOUT A MAINT SUPERVISOR SIGNING OFF A REQUIRED VACUUM LEAK CHECK FOR THE LEFT ENG FUEL FEED SYSTEM.
Narrative: WHEN I RPTED IN FOR WORK ON FEB/XA/08; I WAS INFORMED THAT MR X (SUPVR) HAD SIGNED OFF A VACUUM LEAK CHK JOB PLANNING CARD XYZ FOR THE L ENG FUEL FEED SYS. THIS ITEM WAS SIGNED OFF UNDER AMM REF. THE AMM STATES: TASK 3) TASK: ENG FUEL FEED LINES/COUPLING VACUUM TEST. A) GENERAL: 1) THE ENG FUEL-FEED PRESSURE TEST CAN BE USED AS AN ALTERNATIVE TO THIS TASK. BUT; AS FAR AS THE NEXT SHIFT WORK CREW KNOWS; THE JOB CARD DID NOT GET ACCOMPLISHED. AND WE HAVE BEEN INSTRUCTED THAT THE ACR X JOB CARD ALWAYS TAKES PRIORITY OVER THE AMM. THE MAINT PERSONNEL ALL KNOW THAT THE VACUUM CHK IS INCORPORATED FOR A GOOD REASON. THE DESIGN OF THIS SYS MUST MEET CERTAIN CRITERIA IN ORDER TO ENSURE PROPER FUEL FEED TO THE ENGS IN CASE OF ELECTRICAL FAILURE. EVIDENTLY THE TIME INVOLVED IN ENSURING THIS DOES NOT ALWAYS FIT INTO THE TIME THE ACFT IS DOWN FOR MAINT. THE FUEL TANKS HAVE BEEN CLOSED. NO FURTHER ACTION TAKEN. THIS ACFT IS PRESENTLY IN HVY MAINT. THE CREW HAD WORKED ON THIS SYS FOR SEVERAL DAYS AND HYD SYS CANNOT BE ACTIVATED UNTIL THE FUEL SYS IS CLOSED FOR HYD COOLING. ENSURE IT IS NOT THE JOB OF A SUPVR TO SIGN OFF 'GRAY AREA' OR 'GOOD ENOUGH' FUNCTIONAL; LEAK; OR ANY CHK; ESPECIALLY WHEN THERE IS A JOB CARD WITH STEP-BY-STEP INSTRUCTIONS FOR ACFT MAINT WORK ACCEPTANCE. ALSO; INCLUDE INSPECTION ON SUCH CHKS; WHO HAVE BEEN REMOVED FROM MOST.
Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.